/Engine/Source/Runtime/Experimental/Chaos/Public/GeometryCollection/GeometryCollectionClusteringUtility.h
Get list of child bones down from the source bone at the specified hierarchy level
static void GetChildBonesAtLevel ( const [FGeometryCollection](API\Runtime\Chaos\GeometryCollection\FGeometryCollection) * GeometryCollection, int32 SourceBone, int32 Level, [TArray](API\Runtime\Core\Containers\TArray)< int32 > & BonesOut )